In some countries, for example in the USA, there are regulations which establish that an elevator car has to be operable in the case of emergency (for example when it burns) by the fire department. In the USA, for example, this fire department function (fire fighter function) has to be arranged as a control group in the upper region of the general control panel in the interior of the elevator car. The control group has to lie behind a closable cover. Moreover, it is prescribed that this cover has to be opened by a special key which is, typically, in the hands of the fire department. After the cover has been opened by the fire department with the special key, the fire department has to be in a position to switch over, by the same key, the elevator control to a special mode (emergency mode). This takes place through actuation of a key switch by means of the special key.
It is a disadvantage of the previous installations of that kind that through the use of two identical key switches (the first for opening the cover and the second for actuating the control group) this emergency device is relatively expensive. In addition, if the emergency device is to be modified, for example because keys have been lost, both key switches have to be exchanged for two identical new ones.